1. Field of the Invention
The present invention relates to a communications terminal and a communications system.
2. Related Background Art
In recent years, the digital communication line has been come into wide use, and the communications system making the use of the digital line network, for example, a television telephone and conference system, has attracted public attention. The standardization is presupposed for the wide spread of the communications system. Regarding the video and voice communications, five recommendations have been issued. H.221 defines the frame structure of 64 kbit/s to 1,920 kbit/s channel, H.230 defines the control signal and the notification signal of frame synchronization, and H.242 defines the mutual connection procedure up to 2 Mbit/s. Also, H.261 defines the video coding system of P.times.64 kbit/s (P=1 to 30), and H.320 defines the communications system configuration of voice and video.
Also, the television conference system between multi points currently used typically takes the connection form of connecting each station in star configuration around a connection control device between multi points as the center, as shown in FIG. 4. The methods for displaying the moving picture from the partner station may include switching multiple stations in time division, displaying the picture from the originating station, and setting a plurality of windows to which the moving picture from the partner station is fixedly allocated.
In the conventional communications system, for example, a television conference system, when some fault happens in the terminal device or communication line, such a procedure is taken that the user calls the maintenance department in charge such as a service center, and the maintenance inspector diagnoses the conditions of the terminal device via the communication line and repairs to the spot for the maintenance and inspection if required.
However, in the above-described maintenance inspection, the maintenance inspector had the fault generation conditions explained by the user, supposing the cause of fault within the scope to be understood by its explanation, and often could not correctly grasp the condition of each part when the fault happens, whereby it was time-consuming and inefficient to identify the cause of fault.
Also, depending on the user's knowledge regarding the television conference system, the user may call the service center upon a slight malfunction or accidental fault for which the maintenance inspection work is essentially unnecessary. This is not only troublesome for both the user and the maintenance inspector but also results in a waste of time.